- Creates m_assumed_blockchain_size and m_assumed_chain_state_size on CChainParams.
- Implements access to CChainParams' m_assumed_blockchain_size and m_assumed_chain_state_size on node interface.
- Implements m_assumed_blockchain_size and m_assumed_chain_state_size on qt/intro via node interface.
- Updates release process document with the new CChainParam's values.
Backport of core PR13216.